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Old 01-30-2008, 09:10 PM
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Exhaust tone/downturns question

Hello. This question may be a little odd, but I'll give it a shot.

Im currently running 2 1/4" pipe true duals off my full length headers. From the collector, there is about 3 feet of pipe, then the mufflers. From there, the pipes continue on over the axle and out the rear. However, Im considering putting some downturns coming right off the muffler, to avoid me spending more money to mount the exhaust and put on some chrome tips to get it how I want it.

Now, I can imagine alot of drone, as the mufflers are right under the cab, but will downsturns eliminate this? Also, as a general rule of thumb, will the tone become deeper (or higher, if the muffler is high pitched), or will it become more crackly and high pitched?

Anyone understand what Im asking?

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Old 01-30-2008, 09:58 PM
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I don't know for sure but I can make something up... Here a thread that was started a few weeks back, it might help you out a bit.
Here
And if that doesn't help, I know we have a few guys here that are a lot smarter than me that will help.
Dan
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Old 02-04-2008, 10:21 AM
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I had turn downs right off the muffler before the rear end on a 55 chevy that I had a few years ago and they were quite annoying. Besides the resonating sound in the car, the fumes seemed to stay under the car giving a nice exhaust smell when stopped at traffic lites. Not to mention when I would go places that had gravel packing lots it blew dust every where.
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Old 02-04-2008, 10:49 AM
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I had that same set up on a 73 camaro.And after a few years it rusted the hole back of my car out.I don't recommend it!!!Run the pipes all the way out. (IT WILL RUST OUT YOUR CAR)
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Old 02-04-2008, 11:18 AM
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How about a couple 45 degree angles off the mufflers and come out the side in front of the rear wheels. The noise wont resonate under your body nearly eliminating that drone noise. should look pretty cool too!
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Old 02-04-2008, 04:39 PM
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A "H" pipe (or "X", if you can fit it in) will cut down on the drone a lot.
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Old 02-04-2008, 06:23 PM
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exhaust help?

383 with 2 1/2 exhaust pipes, would a cross over or H pipe help if I'm only turning 6000 rpms max. ?
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Old 02-04-2008, 06:48 PM
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Quote:
Originally Posted by '83Monte
How about a couple 45 degree angles off the mufflers and come out the side in front of the rear wheels. The noise wont resonate under your body nearly eliminating that drone noise. should look pretty cool too!
Id love to do that, however on my broke budget, I dont have a dual exhaust Xmember. So, I have one pipe coming straight back, and the other cuts diagonally.

I could run both out infront of the tire on the one side! I wonder how that would look....
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Old 02-04-2008, 07:00 PM
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I don't think it would look bad to run them both out on the same side.

My pipes and mufflers are ran side by side under my s-10, with turn downs right after the mufflers. The resonance is ridiculous- so I'd suggest coming out the side, or at least running them as far back as ya can, to cut down on the noise.

Nooj
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Old 02-04-2008, 07:07 PM
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Running them both out the side will look good but if you have chrome wheels it will rust them.
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Old 02-07-2008, 01:01 PM
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Ditto on the exhaust fumes. Especially if you tend to drive in heavy traffic. I've also heard bad things when you run out the back and lower the rear window in your SUV. The vacuum tends to pull it back into the car. There have been a lot of new studies on CO poisoning, and damage it causes.
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Old 02-07-2008, 05:15 PM
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i had turndowns on my third gen camaro and they were cool. i loved them, but i am a younger guy and dont really care that much about health or hearing. just make sure you have a radio that will play over the exhaust.
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Old 02-07-2008, 05:40 PM
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It's more about rusting out the a** end of your car.If I new half as much as I thought I did when I was younger.I would still have that nice 73 camaro.Without the a** end rusted out!!!
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Old 02-08-2008, 03:30 AM
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Are you familiar with the term "standing wave?" If you've ever sung in the shower, you know there is one frequency that makes it sound like the walls have shrunk in against your ears. Using turndowns will do that. It will direct the soundwaves at the ground, they'll reflect back up on the floorboards and certain frequencies will drone like crazy.

Great for racers, not so good for street.
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Old 02-08-2008, 11:42 AM
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u could definitely run them both out one side and have it look awesome! I still have a single back and out the passenger side until i get a set of headers and build that cross member too...haha..I think I have that same budget issue you do!..but hey, you can only see one side of the car at a time right?
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